Nano-Implant Could Restore Sight

A team of engineers at the University of California San Diego (UC San Diego)  and La Jolla-based startup Nanovision Biosciences Inc. have developed the nanotechnology and wireless electronics for a new type of retinal prosthesis that brings research a step closer to restoring the ability of neurons in the retina to respond to light. The researchers demonstrated this response to light in a rat retina interfacing with a prototype of the device in vitro. The technology could help tens of millions of people worldwide suffering from neurodegenerative diseases that affect eyesight, including macular degeneration, retinitis pigmentosa and loss of vision due to diabetes.

Despite tremendous advances in the development of retinal prostheses over the past two decades, the performance of devices currently on the market to help the blind regain functional vision is still severely limited—well under the acuity threshold of 20/200 that defines legal blindness.

cortical neuronsPrimary cortical neurons cultured on the surface of an array of optoelectronic nanowires. Note the extensive neurite outgrowth and network formation

We want to create a new class of devices with drastically improved capabilities to help people with impaired vision,” said Gabriel A. Silva, one of the senior authors of the work and professor in bioengineering and ophthalmology at UC San Diego. Silva also is one of the original founders of Nanovision.

Power is delivered wirelessly, from outside the body to the implant, through an inductive powering telemetry system developed by a team led by Cauwenberghs.

The device is highly energy efficient because it minimizes energy losses in wireless power and data transmission and in the stimulation process, recycling electrostatic energy circulating within the inductive resonant tank, and between capacitance on the electrodes and the resonant tank. Up to 90 percent of the energy transmitted is actually delivered and used for stimulation, which means less RF wireless power emitting radiation in the transmission, and less heating of the surrounding tissue from dissipated power. For proof-of-concept, the researchers inserted the wirelessly powered nanowire array beneath a transgenic rat retina with rhodopsin P23H knock-in retinal degeneration.

The findings are published in a recent issue of the Journal of Neural Engineering.

Source: http://ucsdnews.ucsd.edu/

 

Blindness Cure From Stem Cells

The first patient has been treated in Britain in a pioneering trial of a new treatment co-developed by Pfizer and derived from embryonic stem cells designed for patients with a condition that can cause blindness. Specialists at London’s Moorfields Eye Hospital said the operation, described as “successful”, was the first of 10 planned for participants in a trial of the treatment for a disease called ‘wetage-related macular degeneration (AMD). The trial will test the safety and efficacy of transplanting eye cells known as retinal pigment epithelium, which have been derived from embryonic stem cells.

eye2Stem cells are the body’s master cells, the source of all other cells. Scientists who support the use of embryonic stem cells say they could transform medicine, providing treatments for blindness, juvenile diabetes or severe injuries. But critics object to them because they are harvested from human embryos.

This trial involves surgeons inserting a specially engineered patch behind the retina to deliver the treatment cells to replace diseased cells at the back of the eye. The first surgery was successfully performed on a patient last month, Moorfields said in a statement on Tuesday, and “there have been no complications to date“.

The patient wishes to remain anonymous, but the team hope to determine her outcome in terms of initial visual recovery by early December,” it added.

Retinal surgeon Lyndon Da Cruz, who is performing the operations, said he hoped many patients “will benefit in the future from transplantation of these cells.”

Macular degeneration accounts for almost 50 percent of all cases of blindness or vision loss in the developed world. It usually affects people over 50 and comes in two forms, wet and dry. Wet AMD, which is less common than dry AMD, is generally caused by abnormal blood vessels that leak fluid or blood into a region in center of the retina.

Source: http://www.reuters.com/

Blood Clots and Body’s Immune System Linked?

Rice University researchers have found an unexpected link between a protein that triggers the formation of blood clots and other proteins that are essential for the body’s immune system. The find could lead to new treatments for thousands of patients who suffer from inflammatory diseases and disorders that cause abnormal blood clotting.

blood

This link opens the door for studying severe, debilitating inflammatory disorders where the disease mechanism is still poorly understood, including lupus, rheumatoid arthritis, regional ileitis and ulcerative colitis, as well as age-related macular degeneration,” said study co-author Dr. Joel Moake, a hematologist and senior research scientist in bioengineering at Rice. “There’s clinical evidence that clotting and inflammation are somehow linked in many patients, even in the absence of an infection. This linkage could help explain some of the clinical cases that have long baffled physicians.
The research is available online in the journal PLOS ONE.

Source: http://news.rice.edu/